You don't see them in this diagram,

在这张图上看不出来
but if you looked at a real heart you would see that that's true.

但如果看真正的心脏就能看出来
The right and left side of the heart are divided into two chambers,

心脏的左侧和右侧分别被分成两个区域
atrium, ventricle, atrium, ventricle:

心房心室心房心室
left ventricle, right ventricle, right atrium, left atrium.

左心室右心室右心房左心房
The inflows and the outflows are guarded by valves

血液的流入和流出由瓣膜控制
and there are four valves that are important here.

这里有四个重要的瓣膜
There's a valve which is shown by this sort of floppy structure here

这个瓣膜就是图中这个软软的结构
between the left atrium and the left ventricle.

它位于左心房与左心室之间
There's another valve between the left ventricle and the aorta.

另一个瓣膜在左心室和主动脉之间
Same thing on the other side,

另一侧也是一样
there's a valve between the right atrium and the right ventricle,

右心房和右心室之间有一个瓣膜